Antisiphoning device



Oct. 3, 1939. w. C. GRol-:NIGER l 2,174,743

ANTI SIPHONING DEVICE Filed Aug. 3, 1957 '/llllllllllllllll Patented Got. 3, 93

ANEESIIPHONING DEVICE Application AugustA 3, 1937, Serial No. 157,107

' i cnam. (ci. 137-69) My present invention relates to plumbing devices and more particularly to an improved device for preventing back-flow of liquid to a source of water supply. l vMore particularly my invention is directed to an improved device for affording a flow of liquid in one direction only and to prevent return flow of liquid under abnormal conditions, such as the establishment of a condition of vacuum or l`\ low pressure in the liquid supply system.

The present invention is applicable `for use in a variety of situations but has been designed o primarily for installation in a supply system leadlng from a source of potable water or other liquid supply and having a receptacle served by such supply system and the present device precludes the possibility oi any water -which has passed through the device of the present invention and into the receptacle from returning to the supply pipe into the supply system under all circumstances of use.

Preferred forms of my present invention embody a coupling device arranged for interposition PATENT Fig. 4 is a sectional plan view taken line 6 4 of Fig'. 3.

. Referring to the drawing, and particularly to Figs. 1 and 2, lil designates a structure embodying my invention and comprising an inlet end il removably secured to anV outlet end l2 in any convenient or suitable 'manner as by means of threads I3. The end members'll and i2 when in on the assembled position define a chamber i@ within between a supply pipe and a pipe leading to a receiving receptacle, such device being provided with a chamber in which is located one or more arcuately dished annular valve` members arranged to prevent leakage of water upon the ow of water from .the source of supply to the receiving receptacle and to permit admission of air to the pipe leading to the source of supply upon the establishment of abnormal conditions in the supply system. In the device are a plurality of air openings which exceed1 in cross sectional area 36 the cross sectional area ci the supply pipe.

A feature of. my invention is an improved back pressure control device. A

A feature of my invention is an improved device for preventing `returnliow of water which Ii0 has once passed through the supply pipe from return thereto under any condition.

Further features` of my invention will appear as the description of the invention progresses.

In the accompanying drawing:

Fig. l is a sectional elevation oi a structure embodying my invention, illustrating the 'employment of a single arcuately dished annular resilient valve member;

Fig. 2 is aview in sectional plan takengon the line 2 2 of Fig. l; Y

Fig. 3 is a sectional elevation through a struco ture embodying my invention, illustrating the employment of twoopposingly positioned, arcu- 55 ately dished annular resilient valve members;

which is housed a single v alve l5 of ilegible resill0 ient material such for example as rubber. `The valve I5 is arcuately dished and annular in form and its outer periphery is gripped between the cooperating faces of the inlet and outlet ends Il and I2, respectively. The lowerv face of the 15 valve I5 adjacent 'the central perforation I6 therein contacts with a valve seat I'l formed on the upper inner face of the outlet end i2.

The inlet end II has associated therewith an inlet or supply pipe I8 leading from any suitable 20 source of water supply and removably attached to the inlet end Il in any convenient mannerv as by the threads I9. For the purpose of insuring a water-tight joint. between the inlet pipe I8 and the inlet end II there is preferably provided 25 a washer 20 of flexible resilient material, such for example as rubber. The entrance end II is provided with a bore 2l in axial alignment with the bore oiethe inlet pipe I8, and such bore 2l extends downwardly into the chamber I4, and 80 acts to direct water from the inlet pipe I8 into the chamber It. o

The outlet end I2 has attached thereto in any convenient manner, as by a coupling member 22 and washer 23, an outlet pipe -24 which is in 85 axial alignment with the outlet passage 25 or the end I2. i l

Water or other liquid flowing from a source of supply through the inlet pipe l 8 will ilow through the inlet passage 2l, the chamber It, the open,- 40 ing I 6 in the llexible valve I5, and thence through the outlet pipe 2l, to a-receptacle The pressure of water on .the valve member l5 will insure that y the valve member will seat closely on the valve` n seat I'I formed in the lower end I2 and thus 45 prevent leakage 'of water through the perforations 26 in the lower end-member i3. The combined sectional area of the perforations is in ex- `cess of the cross sectional area of the inlet passage 2l of the inlet end II or of the inlet pipe I8. 60 Therefore, if because of abnormal conditions arising in the 'source of supply or in the piping or xtures leading from such source of supply to the supply pipe I8, tending to reduce the pressure of the water therein or to create a vacuum such jet ow of water through the chamber 3|.

asgwould tend to cause a reverse ow of liquid from thereceptacle attached to the outlet pipe 24, the building up of a vacuum will cause the resilient valve member |5.to `lift oft` the seat I1 and air will rush throughthe orifices 2 6 into the chamber I4 and thence through the valve l5 into the inlet pipe I8 and will effectively prevent the establishment of a vacuumcondition sufiicient to cause a return ilowxo'f water through the inlet pipe I8.

Referring now to Figs. 3 and 4v there is shown a device 31 embodying my present invention and in'which said device 21 there is an inlet' end 28 and an outlet end 29 ldetachably secured to the other in any convenient manner as by the threads 38 and which inlet and outlet means 28 and 29 respectively define a chamber 3| therebetween and which chamber is open to the atmospherel 4through the medium of a plurality of openings 'or orices 32. The'inlet end 28 is provided with a restricted opening or nozzle 33 for directiugAlthe so, there is attached to the inlet end 28 an inlet pipe 34, such connection, being preferably removable as by means of threads 35, and in order to positively assure a water-tight connection between the end 28 and inlet pipe 34 I provide a washer 36 Aof preferably flexible resilient material such as rubber.

The outlet end 29 is secured thereto an outlet pipe 31, such securlement being by means of a coupling nut 38 andlla washer 39.

located within the chamber 3| are two cooperating opposingly positioned, arcuately dished, flexy ible valve members, an upper one 40, corresponding to the single arcuately dished flexible valve I of the embodiment shown in Fig. 1, and a lower one 4| positioned opposingly -to the valve 48. The outer peripheral edges of the valve members 40 and 4| arevspaced apart from each other by a spider 42 which' is provided with openings 43 that are brought into alignment with the openings 32 in the open member 28. The normal position of the valve members 40 and 4|, with respect to each other is clearly shown in Fig. 3 where it will be apparent that if water or other liquid is flowing from the inlet pipe 34 into and through the device 21, that the said water or other liquid passes through the nozzle 33 and is directed through the cooperating valve members v40 and 4I into the outlet pipe 31. However, as the chamber 3| will be illled with water the cooperating 4valve members 48 and 4| will prevent an outflow of such water through the passages 32 -Upon the initiation of abnormal conditions in the water supply. system such for example as would cause a lowering of pressure or the tending to establish a vacuum or negative pressure in the system, such negative-pressure will tend 'to cause a return iiow of water in the inlet pipe 34, and a 'consequent withdrawing of water from the outlet pipe 31 into the inlet pipe 34. This is prevented, however, asA upon the establishment of a low pressure of condition of vacuum in the supply system, the valve members 40 and 4I will move out of engagement with each other permitting air to flow through the wall perforations 32 and 43 and such air passing into the chamber 3| will break up or prevent the further establishment of a vacuum condition in the water supply system. As the cross sectional area of the combined perforations 32 and 43 is greater than the cross sectional area of the inlet pipe 34, no vacuum which cou'd arise especially in the water supply system, would'be suilicient to cause withdrawal of water from the outlet pipe 31 back in the water supply system.

Whereas I have described my invention by reference to specific forms thereof, it will be understood that many changes and modifications may be made without departing from the spirit of the invention.

I claim: l

An improved air-break valve comprising a body having a chamber therein and fluid inlet and outlet passages, said body including a portion proclosing position and thereby preclude entry of air into said chamber and under vacuum or other abnormal pressure of the uid to unseat and. effect 

